\begin{table}[!htb]\centering         \def\sym#1{\ifmmode^{#1}\else\(^{#1}\)\fi}         \caption{Construction expenditure and new lane miles, TSLS estimate\label{tab:tableB2}}         \setlength{\tabcolsep}{3pt}         \begin{tabular}{l*{2}{c}}         \hline\hline
                &\multicolumn{1}{c}{(1)}         \\
\hline
\(I^{L}_{st} \) &   0.1584\sym{***}\\
                & (0.0458)         \\
\(I^{L}_{st} t \)  &  -0.0037         \\
                & (0.0025)         \\
\(t\)           &  -0.8271\sym{**} \\
                & (0.2815)         \\
\hline
N               &    1,171         \\
\(F\)           &    20.65         \\
\hline\hline         \multicolumn{2}{l}{\footnotesize Standard errors clustered by state in parenthesis.  }\\         \multicolumn{2}{l}{\footnotesize \sym{+} \(p<0.10\), \sym{*} \(p<0.05\), \sym{**} \(p<0.01\), \sym{***} \(p<0.001\).   }         \end{tabular}\end{table}
